It might be possible to find a used Hobbymat in that price range. The thing that would concern me about the CO is the 5" between centres – if that is correct as adding a chuck and a drill chuck wouldn't leave much at all and what ever people are making holes usually have to be drilled.
Of the Unimats I would suggest the 4 not the SL. I feel that the SL is a little like the Super Adept. They fetch far too high a price for what they are. Same applies to many old lathes on ebay.
Having owned both though the Hobbymat is a much better small general use lathe. Extra bits and pieces are expensive on both. Hobbymat's can have an adjustment problem – people sometimes mess them up.
When looking for used lathes don't forget Gumtree and also Preloved.
Shakes and shudders suggesting this but I suspect your budget would stretch to a Peatol. I'd better duck now as people will be throwing bricks at me over the web. However when I could easily use machines at work it was the first machine I bought for home. Here is a photo of me seriously abusing it working on a Boxford spindle. I have done much much worse things on it.

They have their problems but I don't think they need worry you. As they come the can turn very precise components in all respects. Over time especially if way too much is asked of them the headstock distorts and they will turn tapered components that were once dead parallel. In my case that was circa 0.002" over 4" after some serious abuse with the riser blocks on so that I could fit the part I needed to turn.
I often wonder why I sold it. I did buy a lot of the bits and pieces to go with it. In that mode all sorts of things can be made. Looking at the UK price list they still supply it with a 1/4hp motor but that may have changed. It's generally sold as a kit but the instructions that come with it are excellent.
John
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