One thing I discovered with skimmers is that recirc can be a little overrated for the difference it makes. Thing you have to consider is that if you're drawing water out of the sump and then it exits back into the sump, it's already a recirculation to a degree.
With a little elbow grease you should be able to DIY a mod to recirc an existing single-pass reactor though. The Reef Dynamic models look pretty tricked out, I must say.
Good luck with the search or the mods, whatever you end up doing.
