Good Alternative to Sbooster 12V 0.5A that is less expensive

Hi Don, what component will be using a LPS?

Swagman Labs is probably very similar design to Teradak power supplies.  You can get a small Teradak 12V 2A power supply on ebay for around $130.  I have had good success with using these power supplies.  They aren't the absolute best and the regulator circuit is somewhat inefficient which makes the unit run on the warm side, but it is significantly less than the high end power supplies such as Farad, Teddy Pardo or even Keces.

It's possible they are a similar design, but Swagman will customize a component for you and also offers a premium level LPS which uses Japanese internals. Based in HK.