Today I bought a high-collar zip-front Smartwool base layer from REI. It's great for underneath my synthetic hi-vis winter jersey, and when it warms up a bit it won't be bad all on its own (although I may rethink that, since it doesn't have any pockets.) With the 20% off one item coupon, it was only $64.00
Unlike Performance "wool" jerseys, this is 100% merino wool, while the Performance stuff (even the Pearl Izumi Mammoth jersey) is a wool/acrylic blend.