Hello. Browning Hi Powers have always been made by FN in Belgium with some being "Made in Belgium/Assembled in Portugal" and a licensed copy made in Argentina by FM. FEG makes an unlicensed copy.
I am assuming that the pistol you're describing is one that was marked with the Belgium/Portugal thing.
Generally speaking, guns made before the Portugal thing frequently do have better blued finishes and sometimes better trigger pulls. The current pistols have worked fine for me and I shoot Hi Powers quite a lot. Trigger pulls have not been generally as good out of the box, but I've had no problem in getting good trigger pulls on any of them. Browning's importation of the Hi Power's been reduced due to lower sales in this country. There are just not that many single-action fans other than for the 1911 pistols. For this reason, most of FN's production's actually for the military/police services that still use the pistol, which is declining. These guns' do not require a high gloss blue and the "matte" finish common on most HPs these days is likely also less expensive to use.
In terms of out-of-the-box accuracy, I've had best luck with the newer guns....once you get past the trigger pull. Since the introduction of the MkIII pistol's precursor, the Mk II, the feed ramp's been throated and the newer pistols will feed about any JHP on the market, something that could not always be said about the earlier pistols.
Current prices for brand new Mk III pistols around my neck of the woods has been from about $529 to $550 with two 10-rnd magazines. Assuming that the two 13-rnd magazines are factory magazines, they normally go for around $40 each now. IF the pistol's like new, I'd give no more than $450 for it, but that is because of the magazines. If it had 10-rnd magazines, I'd give no more than $375 or $400 for it. (Part of that is because I have several; if they're hard to find in your area, it might be worth a bit more to you to be able to actually get the gun.)
With loads it likes, expect 25 yard groups of 2 1/2" or less at 25 yards with the loads it "likes." Frequently, these can be smaller.
Hope this is of use.
Best.