Most cheap DIY-style BMS systems (such as Mini-BMS) are meant for LiFePO4, so a different voltage than what you need. That first link is meant for GBS (nominal 3.20V, shunting at 3.55V). I don't know for sure, but I would guess that your batteries are nominal 3.80, and max charge 4.2V, which is typical for, say, the lithiums in a Fisker Karma or something like that. The second link looks like it may be fully adjustable, but you would have to contact them to be sure.
I would go the fully DIY route. Learn Arduino if you do not already know it, and come up with something yourself. That way YOU know exactly what you are getting. I would bottom balance and then rely on an Arduino based system to provide voltage warning (at an individual cell level) and to control charging. Low cost would be a nice side effect - probably under $100.
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