If all you need to know is where to start pricing it, then I'd treat the rivet holes as having "no effect on price". Other factors (brand, production period, diameter, weight, profile, condition) have a much greater influence on price provided the holes are done to a "professional standard". Professional standard means clean drilling (e.g. no tracks from dancing drill bits when using a hand held drill), evenly spaced, and so forth. Of course if an older cymbal has had rivets in it for years there will be surface wear from the dancing rivets. That doesn't make the holes "unprofessional", just well used. ;)
I suspect that the mechanism by which the presence of rivet holes may very slightly lower your expected price is indirect. The potential market is reduced by those who don't want a cymbal with holes, and it is the slightly reduced market which may lower your achieved price. I don't have the stats analysis to back this up this assertion quantitatively (alas I wasn't coding info on rivets systematically in my 7 years of data from eBay and I can't go back and add it now :( )
Unless you have the original receipts for the cymbal one can't be 100% sure the holes are "factory". The distinction one can make from the cymbal alone is if they appear to be done to a "professional standard". That's a more evidence based way of describing the situation unless you can produce the receipts. The other situation is when the cymbal has an ink stamp on it which says "SIZZLE" as a model designation. I've added this just for completeness, although I don't think that applies in your case. Of course, absence of ink saying "SIZZLE" doesn't mean it never had such ink. It may have gone missing over the years.
Good luck with the sale.
