I finished a California King 2" (1.5" finished) with no repeated charms for a Postage Stamp Quilt (PSQ) which I collected & used Thousands of charms from Quilting Board (QB) as well as two other sites online. It has been quite a while since a true 2" swap happened on QB. Charms are easily chained together into rows, lining up the rows is fun, & the joined points are very forgiving.
Wish I had time to host a QB swap but very busy with UFOs for 2018.
Chytazie could always cut 2.5" squares down to fit their needs.
Hope this helps!
hugs,
dj