This is an interesting question, because I've rebuilt several Crosman 357 and a few 38's. The 38 came out long before the Crosman 357's. When Crosman developed the 357 for sale they stopped production on the 38's and dropped all the parts for it, EXCEPT the C02 parts. Three of the C02 parts are common between the two pistols. All 357 parts began with the number #357 and all 38 parts began with the number #38. If you look at the parts diagram for the 357 you will see three parts starting with #38. These three parts are interchangeable and can still be ordered from Crosman. (see the links below)
Crosman supplies parts for all their current airguns.
Now if you don't want to go that route then Crosman offers a free service to locate shops that repair older Crosman air guns. See the links below.
Crosman offers a service to locate shops that repair older products. See this link. http://www.crosman.com/general/find-a-service-center
Crosman offers a free service to locate shops that repair Older Crosman products. See the link below.
Crosman offers a free service to locate shops that repair older air guns and rifles. See the link below.
This pistol was made between 1978 and 1984. Crosman no longer supplies parts for this model, But the offer a free service to locate shops that repair older Crosman air guns. See the link below
Bad seal. You can buy them at basically any parts store...
10-125 USD
Crosman has the information online. See the link below
Crosman offers a free service to locate shops that repair older Crosman air rifles. See the link below.
There are several independent shops that repair older Crosman air rifles. One of them may have what you need. Crosman offers a free service to direct you to these shops. See the link below.
Crosman still has parts available for this model. You can order directly from them. I've attached a link below of all the Owners and parts manual for Crosman rifles. (it's a Crosman web page) Find your model and open the parts diagram Then call Crosman customer service and order your needed parts. Crosman is spelled with One "S"
Not really. It will leak out eventually. Besides by leaving a charged C02 cylinder in the pistol keeps pressure on the seal and this may damage it over time. I always take the cylinder out of the pistol when I am finished shooting. No matter how much C02 is left int the cylinder. It doesn't cost that much to put a new Cylinder in the pistol when I want to use it again. Besides leaving it in the pistol will eventually reform the seal. I want it to return to a normal shape between shooting sessions. Is it cheaper to buy a new cylinder or have the pistol repaired because the seal is warped.
Buy a replacement seal kit Follow the directions included If you do not have the background knowledge needed to work at this level you are not qualified to safely do this work.