I have one, it's an LK210. I didn't get it from this seller but here's an example -
https://www.ebay.co.uk/itm/High-Qua...637960?hash=item33f474f608:g:CSgAAOSwW75cwAav
There are several around. My advice would be to get one with an internal back up battery apparently the LK210 is 4 hrs.
These are very simple to fit and very easy to use. There are a few video's on YouTube - one quick one is here -
There seem to be several sites shown this unit - one such is
http://www.xeelectech.com/e_products/GPS-Motorcycle-tracker-3.html and another is
http://www.tk-star.com/
I use a GiffGaff sim with a top up app on my phone, just need to send it a text (sending 'where' gets a location with google map link) once every 3 months to keep GiffGaff happy.
I found a set up doc on a forum (this is not mine so I can't be held responsible blarr blarr blarr…) anyone can get this from my OneDrive -
https://1drv.ms/b/s!ApNQJ5VPU_vSwALHnc-AdfP3TZY-
I also found a free.. yes free tracking site -
http://gps-trace.com/en/index.html - you need to log in at least once every 6 months to keep this active and guess what I've not done... yep.. Would be great if this could be used with Spotwalla.. I ran the unit with GPRS on and tracked it for about 4 days and it used only pennies data if I remember right, that was last year.
Hope this helps...any questions happy to help.