Vvt-I Oil Problems

[2nd vvti engine!!]

hi all

I brought my celica 3 years ago the first week I had the car I covered roughly 200 miles and used a sump full of oil causing the 2 big end bearings to go.The garage got it repaired fair enough not a problem until 5 weeks ago it used roughly 3 letters of oil in 60 miles I didn't check it for a few weeks "my fault!!" I took it to a local engine repair garage and was quoted £1700 for a total re build. I went on to 247parts and they put me on to a dealer selling a second hand one with 43,000 miles off a 05 celica for £600 I brought it and then paid £350 to have it fitted I got the car back 2 weeks ago and with in that 2 weeks I have used 4 letters of oil and covered only 240 miles its totally sole destroying.The company I got the engine off hasn't got back to me I have phoned them every day over the last 2 weeks and they just say "there's no one in the office we will call you back!!" also no response to letters sent recorded delivery I only had a 60 day warranty on the engine and its slowly running out if there's any one out there please give me some ideas I'm at a total loss

thanks

Chris