The ZUM Spot and TGIF ones are using free Pi-Star software, in the case of the TGIF board, it looks to use an ordinary MMDVM board that can be bought for $20 to $30 on eBay.
I recently configured a cheap Chinese MMDVM board and found their $0.12 TCXO drifted all over the place, however the replacements are available from Mouser for $2.39 with a ten times more stable unit!
The size and basic specification of the original Chinese 14.7456 MHz TCXO by SCTF is the same as an ECS-TXO-3225MV-147.4-TR. However, the ECS one is specified as +/- 2.5ppm over -30C to +85C, as opposed to 20ppm for the Chinese one (assuming the Chinese one originally fitted to my board even meets their claimed spec). Obviously a board without an OLED display is easier to work on, as the TCXO sits under the display.
Configuring your own hotspot is a lot less expensive than buying a ready to use one, especially if you know which end of a soldering iron gets hot... A cheap hot air soldering station is handy to swap the TCXO too. Any of the later Raspberry Pi boards can be used with these boards, many of us have a few in the desk drawer, unfortunately sourcing new ones at the moment is a problem, but millions have been sold and many of those are likely to be gathering dust.
73 Dave