Solar Charge Controller question

Here's my set up:
2018 Coachman Viking 17BHS 21'
Dual 6v batteries

Solar panels:
2 Nature Power 100 watt Polycrystalline panels
Tolerance: 3%
Voltage at Pmax(Vmp) 18.0V
Current at Pmax(Imp) 5.65A
Open circuit voltage(Isc) 21.6V
Short circuit voltage(Isc) 5.74A
Max system voltage 600VDC
Protection class Class A


I'm looking for a decent yet budget minded (Under $100) Solar Charge Controller to run my system.


Thank you!
Brian