You might be able to pull off a Jardini in that size tank, but nothing else. Not saying to do it though, Jardini still should have 2.5-3' wide tanks because they are as flexible as other arowanas.
It would just have a long time in that tank before it had to upgrade
You might get lucky. I got my 6x2x2 for £100. I then had to spend £100 on a 2nd hand eheim 2260 and about £50 and a weekend making a lid. Go bigger if you want an aro, it seems once you go over 6x2x2 in the uk not many people have the space for this size tank and hence have trouble shifting them. Keep an eye on ebay and aquarist classified.
You see 6ft tanks on aquarist classifieds for around the £100 mark regularly, you also get people who think that because they paid a grand for a new tank a year ago that it must be still worth at least half that now.
Here 2nd hand tanks are next to worthless and I always get my laugh at people who sell used 2 and 3ft tanks for more than a new one cost from pets at home.
Ebay is the next best place but also look in adtrader and other classified ad sites on the net.
£60 might be pushing it but you will probably come across one sooner or later if you are patient. Buying a new 6ft tank is not that expensive either, around £300, and it comes with a guarantee should it break. Might be worth saving up.
I have a close personal friend that has kept both a adult jardini and later a juvi silver in a 6ft 120 gallon. The lived and by all appearances were healthy but It was too confined, They often tried to jump out of the tank and eventually did while my friend was at work.
His (very expensive) loss was a valuable lesson for me, I picked up some oscars instead =)
im a 15 year old and this tank is going into my bedroom, so unfortunately i cant quite get an 8x3x2, haha! thanks for all of the feedback, though. I'm really stuck on what fish to get. i want something a little more adventurous than oscars -_- is there any other suggestions that would be able to live in a 6x2x2? it's hard to pick when there is such a big choice :O
6x2x2 is plenty of space for the less extreme monsters, i hope you have a downstairs bedroom! Frontosa colony, grammodes pair, massive clown loach shoal, some lungfish, 1000 guppies! could go native and get perch or tench.