Hi,
yes you are right,snap on welders are made by cebora in italy,you should be able to find a dealer locally,im pretty sure that BOC are agents for cebora,or i know there is a guy that often advertises spares on ebay,hope thats of some help.
the trigger on the handle is broken, as well as the plastic square where the wire feed mechinisim is with the sprung clamp - i dont know what its called, but can take a pic.
Cebora, taskmaster, or snap-on are all made by Cebora like was said earlier.
I have a taskmaster 130 turbo (which im sure is the same) and Ive already repaired it with pieces ordered through my then local snap-on dealer, theyre expensive but you can always find one localish...
For the plastic wire guide block, I bet its the posts that hold the floating guide onto the block, mines snapped one off too, and for the interim I just apply a clamp gently around the mechanism to get the feed pressure correct on 0.6 wire. I used a snap-on torch for my replacement torch/tubing, its a bit of a job replacing it as you have to open up the main welder casings, but its not rocket science. Trouble is, with the snap-on torch, it was almost cheaper to buy another welder...
I found out that an enay return, was more expensive than the replacement parts. So, £21 later (weld air supplies in dunstable, great service and very cheap) and the camper is back on track, and my garage is glowing like a prop from 'back to the future'.