When I wanted a 5mm round spessartite I contact Dan at customgemstones.com and he cut me one. It turned out marvleous! Maybe contact him to see what he might have in spess rough.
Depending on the price... I bought a lot from GemSelect for a project and their stones were true to pictures and pretty cheap. They do not sell in pairs but you can mix and match... It is well worth to look at their website.
Believe it or not, the best, most intense orange spess I have, without any yellow, brown or red modifier, I got from Worldgemstone on ebay for cheap. It was one of those things where I got a few stones from them about a year ago, and two were a case of you get what you pay for, and the pair of round spessies I bought made the meh spinel and whatever else I got totally worth it. I have not bought from them since, but I have checked back regularly for more small spess pairs.
I already have a pair of 7mm red garnets, then looking for the 6mm spess, to be followed by a really neat pair of 5mm yellow/gold sapphires I've had for quite a while.