Go custom. Call Bruce at Coiler or Sean at Donek. I ended up going with Bruce, mainly because I am in Canada too. Got exactly what I wanted, built for my weight, height, terrain, bad knee etc... Custom topsheet and totally worth every penny. FWIW, I ended up with a 171 and I'm only 155. The extra 7 cm compared to the 4wd that I just sold gave me a lot of extra stability and the turning radius can be customized for your narrowness.
Boots: try them on. See if anybody local has the Deeluxe, Head, or UPZ shells even to try on. You could use your old liners to reduce some variables and see where the pressure points on the shells are.
N.