uBitx (http://www.hfsignals.com/index.php/ubitx/) is I think $110 for a kit of the guts. People seem to be really enjoying building them.

QRP Labs has a bunch of cool projects (https://qrp-labs.com/qcx.html). CW is something I haven't learned yet, but is pretty attractive for what it can do, how far it can reach on low power.