There was a thread on here a couple of weeks ago about the 400 where it was mentioned that they can be found fir around the £250 mark with case & accessories. Not too sure on the possible cause of your ones issues but I think parts are very hard to find if it needs anything replaced other than seals. So, less than 250 but it could be a lot less if it cannot be repaired, maybe someone knows what the possible cause of it not cocking are & can give an idea of repair costs to factor in.
Nice pistols though.


The old thread might be worth a look.