Small Claims Court sounds like the way to go.
Any claims below a certain amount (£5000?) can be made, effectively, risk free.
If you lost (highly unlikely if you put forward a clear, well-researched, claim) then there is no risk or cost to you.
It will only cost you a nominal amount to register the claim and any expenses involved if you wish to attend. Choose a County Court near to yourself so you don't have to travel too far. Also makes it more difficult for the defending party to attend the court.
Put your claim paperwork in as late as possible with respect to the closing date for submission - gives the defendant less time to submit his defence. The defendant must see anything you submit before he defends himself.
A very simple procedure - just requires a bit of effort.
You may not see your money again but you will get the pleasure of a County Court Judgement (CCJ) against him. This makes life more difficult for him in respect of future business credit, mortgages etc.
Myself and a couple of partners were taken to the Small Claims Court in respect of a PFA aircraft we sold some w****r. He flew it for 70 hour over 4 months then decided there was something wrong with it. Tried to sue us for just under £5k (£11.5k aircraft). We prepared well, stated the facts and the case got thrown out. The aircraft, needless to say, was in pretty good nick (for a 51-year-old aircraft) and had a brand new Permit when we sold it to him.
The Small Claims Court works very well and allows you to make a claim at no risk.
Whether you see your money again is another question.