Divx players are MUCH cheaper than dvd players. Why I don't know. Maybe they are just designed to be cheap and not full of promises about being fabulous. The prices at dvd.co.uk fluctuate but Trek is incredibly cheap atm. I have bought several seasons of Dr. Who there which were easily 1/4 of the price at JBHiFi. I've bought all my TOS and TAS there. Excellent company.
Your other option is to give someone who owns the Trek you want a USB so the can put the eps on it, assuming they can rip them to their computer. That may be crossing a copyright boundary for you though.