Looks my my last reply was caught in the moderation queue... Mods, if you see this, disregard the previous post.
Thanks for the responses, everyone. I measured my head circumference yesterday, it's about 22.5 inches. I have a friend with an Epic Cosplay wig, I tried the wig on last night and it fit alright but I wouldn't go much smaller. Looks like Cosplay.com's wigs are too small for me without performing the modifications - thanks for letting me know about that by the way, I'll go searching for the post.