Given that this is a bronze age comic of a fairly popular title, one would have to think a ton of Hulk 181s exist, with many high grade copies to boot. Predictably, as the prices go higher, more high grade issues are coming out of the woodwork. On eBay at this moment, we see
Hulk 181 CGC 9.6
Another Hulk 181 CGC 9.6
An unslabbed copy claiming to be NM/M (uh huh...)
CGC 9.0 with a $1,120 Buy-It-Now
Plus 12 other slabbed and unslabbed copies in lower grades. And this is supposed to be the slow time of year for online sales!