As Rob say Cliff,
If you are capable of using a few tools it can be rewarding to do it yourself. (and you learn a lot about the pistol at the same time).
Unfortunately, because I do them, I haven't had the opportunity to look for someone to do them up, so can't help mate, sorry.
Russ
Air Arms S400 Classic - Hawke Airmax 3-9x40 AO MAP6, SMK QB78 DL - JSR 4x40 Mildot ill.El Gamo ASI sniper, BSA Airsporter MkVI. UBC#22 - Sheridan EB22, Gamo Compact:R77-4:Falcon, Walther PPK, CP88 shiney, SMK G10, Baikal 53M:MAK, Crosman 357