I can tell you this:
1) Good stainless steel can be polished and finished to appear like good chrome. There will be a slight different color to the metal, mostly visible only when comparing side by side. The new OEM wheel covers from MB are highly polished stainless steel and they look every bit as good as chrome.
I can't tell you how good the Harrington Stainless bumpers are, though, as I've never seen them. But the MB-OEM wheel covers are a great example of how SS can replace chrome, and do it well.
2) It's been said before and I'll say it again: chrome plating, or shall I say, re-plating is expensive.
It's a misnomer to think that you can choose the price based on quality on some kind of sliding scale. Just about the only people doing chrome plating are those doing it decoratively and custom; there is a certain quality level they do and that's it. I'd be afraid of one who would adjust down his quality and price.
3) Anybody should be able to fill in the holes and grind them smooth. That's the easy part!
Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored