Free(er), for now, until the next "variant"
Are there any RV dealers near you, that were Roadtrek dealers before the Hymer take over? Maybe someone at one of them can tell you, if they still have service staff from way back then.
Or, you could measure the base of what you have and ask at an RV parts shop.
Mike. Comments are anecdotal or personal opinions, and worth what you paid for them.
2018 (2017 Sprinter Cab Chassis) Navion24V + 2016 Wrangler JKU (sold @ ????)
2016 Sunstar 26HE, V10, 3V, 6 Speed (sold @ 4600 miles)
2002 Roadtrek C190P (sold @ 315,000kms)