One place I WOULDN'T take it is Ivor Searle in Soham, Cambridgeshire. They reckon they're the biggest remanufacturer of engines in the UK. Well this may be true but I had a very bad experience with them. I took my Supra Cylinder Head & Camshafts to them for machining of the Camshaft Journals, Cylinder Head and Bearing Caps. What a mess they made of it. I sent them a letter but got no response whatsoever. I should have pursued my case but I'd really had enough of the whole thing so I just ket it go and remedied it myself. Here's an extract from the letter I sent to them outlining the problems with the work they did for me:
...
(1) Location dowels only partially inserted in the cylinder head and misaligned by a considerable amount.

(2) Elongation of the dowel holes in the bearing caps due to the above.

(3) One dowel hole distorted so much (approximately 1mm) as to leave just enough material between the dowel hole and the journal diameter to form a knife edge. And creating a crack in the bearing cap between the same.

(4) Swarf particles up to approximately 2 sq mm in area each, embedded in the bearing cap mating face of several caps.

(5) One dowel very badly damaged and marked with a pattern very similar to that found on the majority of vice jaws.

(6) Camshaft journals which still had deep scores in their circumference after explicitly advising the 'Engineer' that I wanted all of the journals to have the minimum amount ground off to clean up.

(7) Two studs which appeared to have been removed with ‘Mole grips’, therefore having damaged threads which needed rectifying by me before they could be re-fitted to the head.

I was very keen to return the engine to a working state as soon as possible and therefore continued with lapping the valves in and cleaning the cylinder head and camshafts of swarf and lapping paste etc. To put my mind at rest I thought it would be wise to check the fit of the camshafts in the newly machined cylinder head and caps without assembling the valves into the head so that I could get a true feel of the bearings without spring compression clouding the results. I duly assembled each camshaft into the head and found that I couldn’t turn either of the camshafts by hand, even with the extra torque afforded by the cam belt pulleys. I therefore assembled each cap in turn to see which were the offending ones. As I fitted each cap in turn I measured the torque required to rotate the camshaft. Some could not be turned by hand but were less than the 6 lb.ft. that I could measure. Of the fourteen caps, only three, when assembled and torqued down to the correct value allowed me to rotate the camshaft satisfactorily by hand. The three worst caps required approximately 7.5, 23 and 40 lb.ft. of torque to turn the camshaft, these figures being attained with lubricated journals. I therefore spent approximately nine hours on the Sunday having to scrape in each bearing cap by hand, not something I expected to have to do after having the assembly machined by ‘experts’ in this field of engineering. It was obvious from the pattern of the high spots on the caps’ bearing surfaces that the caps had been distorted when fitted to the head for subsequent machining of the bearings. This distortion was most probably caused by clamping down on the swarf which I had found embedded in the mating face of the caps....

This was back in September 1997 so maybe they've improved since then but I don't think I'd risk going to them again. I hope you have more luck finding someone decent.