I recommend you go online and do a web search for "Air gun repair" and locate a shop that repairs your model, or see the following link.
http://www.airgunarena.com/index.php/Repairs/Parts
Yes, the Spitfire was an excellent fighter.
Blue Book of airguns says "typically between $150-$200 price range."
lets start with. Who made the rifle? there are over 100 different companies who have made air rifles.
You can still order 1077 parts from Crosman in New York. See the parts and owners manuals link below. Then contact Crosman Customer service and order your parts.
Crosman still has parts for this rifle. contact Crosman at the link below (Customer service) and order the parts you need.
The Crosman 140 Air Rifle was made from 1954 to 1968 in four different variations. Crosman no longer makes parts for the rifle but you can still get it repaired. The Crosman home page offers a "Find a repair center" button on their first page. From there you can locate a center that has parts for your rifle. See the related link.
Many Air Forces used the Spitfire. Principally, the Royal Air Force, but also the US, Canadian, Australian, New Zealand, Russian, South African, Belgian, Dutch, Norwegian, French, Portuguese, Greek, Turkish, Israeli, Egyptian and Indian Air Forces.Ref - 'Spitfire, the story of a famous fighter' -Bruce Robertson.'Spitfire, a complete fighting history' - Alfred price.
Crosman does. see the link below for the parts list and how to contact Crosman.
Crosman owns both the Benjamin and Sheridan line of air guns. See the link below for the Marauder parts list and the customer contact page for Crosman ( They sell parts for the PCP rifle.)
Go to airsplat and you should find what your looking for. Or you could look up "air gun repair" on the web.
The spitfire's first flight of the spitfire was on the 5 of march 1936by "Mutt" summers and the last flight was in 1961 by the irish air force
Crosman still supports this model and has parts. See the links below.