To simulate the Cdn semi gloss olive, I have added a bit of black to the usual mixes of semi-gloss olive. Makes the colour a lot richer. Try adding a little at a time until you get a match that you can live with, keeping track of how much you added, then make up a pint or quart with that ratio.
Frank: We have discussed the two colours of olive many times on this forum already. I have had decent success with using 34070 for the olive, and 383 Carc substitute for the flat green. It won't look right until at least a couple days after the paint job. In the end, those original IRR paints went through a hugh of colour change in service, so if your colours are out a little, they will just look like they have been on there a little too long.
Here is an example of the two green on my MLVW and Jeep (no idea who the kid is in the Jeep....definitely not me).:
