Yeah, they are hard to get. I traded My Pin 80134 for Pin 75768(Sebastian ptn) and I don't regret it since they are gorgeous pins, well made and great combination of colors. But I meant I had to give something good for it, my grail was Pin 58990(samba PTN) and I was able to traded for a LE 250 jumbo vinylmation and a wanted LE 300 event peter pan pin, but I am happy with the samba when I got, I love it. I recently bought Pin 79110 and another simba PTN(since I finally got mine through a trade I bought another one but forntrading not my collection), and they are both up for trade, I would trade any of them two for the Rey re PTN Paris or the Ariel, or anything that is highly wanted in my list.
So my best advise marcia is to:
1: if they are not your trails, stay away from them because most likely u will not be able to trade for them without trading something that u will trade for one of your grails.
2: if u really want them, well buying them will be the best option, that option doens't apply to me since I like to trade for my grails and most of my pins, but rally that is the easiest way, but not cheap at all.
3: what other people said, try to trade for the least wanted ones and work your way up to a more wanted one and so on.