>>479211depends a lot on budget dude. the little green one was a'bush chucker' from Gamekeeper Catapults ( just google and it brings up the site) The guy who makes them is sound (I live just up the coast from me actually) but has a massive lead time ( like 8 weeks+) as he's so busy making them. Prices are so so but he uses 'safe' materials for construction like birch crossply or HDPE as opposed to some sketchy grained wood, or chinese monkey metal that some folk sell ( grain is not even, and prone to breakage, the for snaps and comes back to twat you in the face- not good)
If you're new to shooting ( I've been into it for a few years now) I'd look at something like the Flippinout Scout (again Google it should bring up a link for a UK seller) - it gives you a lot of options for band attachments, and grip styles so you can experiment a bit to finds what's best for you .
Remember though with cattys, it's the shooter, not the catty so much, I'll hit 9/10 where I aim every shot, but I'm only a fair to good shot really. I'm on a few of the more sketchy FB catty groups and there are some guys on there who can make scary ass shots with stuff they hacked off a bush and tied a set of bands to 5 mins before shooting