For about $50 US, you can get a 10Gbase-T SFP+ module that gives you a copper port at 10gig within a SFP+ form factor. That, coupled with a cheap Mikrotik switch, is plenty to get started.
Second hand Brocade ICX switches are also plentiful and not too power hungry (but they can be loud).
Second hand Brocade ICX switches are also plentiful and not too power hungry (but they can be loud).