OK so you have a 405 XUD9 4 door saloon with non-metallic paint. With Power steering, without ABS brakes, with a sunroof, and tinted glass all round, electirc front windows, no air con and simple central locking.
You need a 515G3. Diameter 156mm 6 ribbed belt.
Do you want it? How we gonna do this? I live in Gloucester and you live in Addlestone. I could send it to you though I have no idea how much the postage would be at the moment. Cost of the part is around £95 including VAT.
As for the steering gaiters. Yes the O/S is easy. I do recall doing a N/S one years ago and it was hell. I used the peugeot boot and after much cussing and swearing managed to stretch it over the ram fixing. Not a job I would want to do as a cobble!