RBS20 alternative

[jkeun]

Since a year I use the RBK23 system, which has the router and two satellites. I now want to add another satellite (RBS20) to it, but can't find this anywhere (at a decent price). This also goes for RBS30 and RBS50.

Is it possible to use a netgear wired access point and add this to the mesh system? Or am I ending up with two different SSID's or manual switching between signals? 

[FURRYe38]

RBW30, RBS40v(oice) or EX7500/7700 or 8000 extenders. 

[jkeun]

All Wifi5 sattelites seem no longer available (at least new). If I add a wired access point (f.i. WAX214) on the third floor, does this also works seemless? 

Or do I then have to switch between SSID's?

[FURRYe38]

If you set the WAX214 on same SSID and PW and used different channels from what the Orbi uses, then devices should connect fine on there own.