Hi mate they are a good little gun for the bunnies used my mates a good few times.
Bit of a problem with subs now and agian, jams, but I think that is down to cleaning!
Wax off the subs, powder build up an the velocity it copes with HV ok!
As for the mag you could try rimfire magic and I believe the is a site somewhere purely with trick stuff for these rifles!
This one is in USA!
http://andean-inc.co...22magazines22lr
One from UK
http://www.rudefatdog.com/10_22.html