Valve guides on a 2.0L

[MontyQ]

I got a call from the machine shop working on my heads, they want to replace all the valve guides as the ones in the heads are loose. The problem seem like someone has been in there and done that before, but with some odd sizes - currently the machine shop says these are the diameters of the guides in(mm):

0.478(12.1412) 2 of these - Intake
0.482(12.2428) 2 of these - Intake
0.600(15.2400) 2 of these - Exhaust
0.596(15.1384) 1 of these - Exhaust
0.607(15.4178) 1 of these - Exhaust

This is a very reputable machine shop and they are trying to help me keep costs down by letting me chase the parts. My first question is that these seem to be fairly oversized already and also non-standard. Any ideas on where/how to find replacements? The machine shop said to hit these sizes or just a bit over (they can machine them down if needed).

Thanks, Monty