If you need VPN, how about setting up a pfsense firewall and use it for OpenVPN? There isn't an arbitrary limit on the number of clients, it's just up to your hardware. Surely you have a spare PC with a couple nics hanging around. Give it a reasonably current PC with a reasonable CPU and you ought to be fine. My very modest home network does fine with pfsense even running on an old pc with 2gb of memory and an Athlon 64 3200. Release 2.2 is out, based on FreeBSD 10.1 (current production release).
In fact, I have been using pfsense as my firewall for a year or so now, and I hang my wireless routers behind it - and just use them as access points. Easier to power cycle the wireless boxes when they get flaky, and it doesn't disturb the wired connections. Plus, save the pfsense config, and you can move to a faster box if you find any resource constraints. Or throw in a new pc if the old one croaks, very little down time. Or add a second box as a failover. Or... you get the idea. :-)