Hi @Slydoggrx, these will probably go on sale at the end of this year. The design of the casing is however just open source, so you can also print it yourself, buy a raspberry Pi and install the software.
A node earns nothing. Grin does not use a secure or master node system (in which case you secure the network by staking), so a node is just there to strengthen and validate the network and for you to validate your transactions if you install it together with the grin-wallet (rust implementation), so you can have your wallet on the Raspberry Pi.
If you want to earn Grin, the best way is to mine yourself using a G1 Mini miner from Ipollo, they are sold via Nhash, see this link for more information:
Be ready so shelf out some money though, they are 900$ or so.