You can have a go at moving your roses when they are dormant, so sometime from November depending on the weather. Try to make sure you don't include any bindweed root with them. (Horrible white fleshy things, easy to see)
Still thinking about how to disentangle the bindweed from the hedge. Mature roses aren't very keen on being moved though, so get the person who moves them for you to do it carefully.

How long and wide is the border? Are you intending to empty it after the roses are moved?

My garden's been suffering from my poor health lately too so sending you lots of fellow feeling

if you peel some bindweed off the hedge onto the soil/path, leaving it rooted and then spray it with something like round up at this time of year it will take the weedkiller down and start to kill it off that way. it wont do it all in one season though but it will weaken it. do you have a jobbing gardener who can dig the white fleshy 'roots' up. then next spring as any new growth emerges keep digging bits up.

Also when you lift the roses prune them back to about 1-2ft tall so they are less likely to be damaged by the winter weather.

Don't know how much space you have but if there was someone you could trust you could swap the use of an area for, say, veg growing in exchange for a couple of hours of general maintenance

Bindweed and ground elder are notoriously difficult to get rid of, the only way to deal with it is to keep digging it over and over again and eventually you will win the battle, but because of your health this is going to be difficult, applying weed killer on bindweed in my experience is a complete waste of time, it will only go so far down on the roots, your border could be full of deep matted bindweed so weed killing would be a waste of time, the roses should be ok to lift in late Autumn and potted into good sized planters, well rotted manure, compost and soil, give it a good mix, plant and prune, the border could you gravel this area?, if so then you could get someone in to do this for you, the border once cleared would have a decent membrane and 20 mil gravel, it’s not that expensive, ton bags of gravel average between £45 to£50, on the gravel you could place various pots of roses or other shrubs, this would be maintenance free for you, and one less thing to worry about, if you choose to gravel then ask around as a recommendation is far better than getting someone out the paper.

Weedkiller does work to a certain extent but you have to do it several years in succession. The roots aren't called Devils Guts for nothing...they can go down six feet.
I wondered about giving up on the border for a year or two and laying it to grass -(You might have a few pots instead) -mowing would deal with both weeds except for the remaining bindweed on the hedge which would yield to Bamboo's treatment after a few years.

Sorry Steragram but growing grass over Bindweed, just does not work. We have it coming up in the lawn(soi dit) here from the border which was absolutely smothered in the stuff. Trouble is, even the Lawn Weed killer does not seem to be reducing the incidence of it in the grass (moss).

Oh dear - I thought really regular mowing will kill a lot of would-be tall things - it certainly works for brambles. Another good idea bites the dust then, sorry!

Its disappointing that you new smaller garden is causing problems.

My heart goes out to you, my veg patch has been invaded by bindweed too; it arrived in the surrounding beech hedge and has spread like wildfire despite my efforts to dig up the roots. My heart sank when it reached the greenhouse last year. My soil is primarily clay so rather claggy when wet and rock hard when dry ..... lovely to work when friable but our climate makes catching it in that state tricky, this year has been better than last. Age-wise I am not far behind you and find as time passes arthritis is making gardening more difficult too ...... and our green (garden waste) bins are emptied fortnightly which isn't often enough either :-( I hope the thought that someone else is in the same boat will bring some comfort .... my thoughts will be with you as I mine the Devil's Guts :-)