I would look to the internet and do a search for 'Airgun repair." there are several people who repair airguns of all types. (see the link below.)
Crosman still has parts for this rifle. contact Crosman at the link below (Customer service) and order the parts you need.
check the link below and contact customer service. Crosman list that some parts are still available for this rifle.
Yes Diana RWS rifles are still made. See the link below.
What condition is it in. That determines the value.
Unfortunately, you will probably have to find another rifle to cannibalize for parts. --------------------------------------------------------------------------------- I suggest that you go on the web and search for Air gun repair. There are several places that repair out of warranty air guns and rifles all across the US.
I would contact Diana directly at the link below and see if they will send you a diagram.
It depends on who made the rifle. Check with the manufacture. OR, Look online for shops who in specialize in "air gun repair." The are all over the country and make a living repairing out dated air guns and rifles.
If you are talking about the Crosman Nightstalker you can go to http://crosman.com/site/manuals_crosman_rifles To see the parts list. Or just contact www.crosman.com (Customer service.) They still do repairs on this air-rifle.
As far as I know Crosman has made a 1077 rifle and a 1377 pistol, but never a 1177 model that I know of. However Crosman offers a service to locate repair shops that repair older air rifles. See the link below.
What condition is it in. That determines the value.
You should try looking at your air hockey table manual. They usually have the specifications and where you could get their replacement parts.
The Dians model 22 was made between 1927 to 1940 then again from 1953 to 1985. Both models are similar but totally different in parts