1/24 F1 Chassis. A version of the 1/24 F1 chassis, less motor, is available from Professor Motor if you hunt hard enough. Yep still $$$ at $145usd w/o body or motor.
1/32 F1 AllSlot replacement chassis. $15
MB Slots offers a fibreglass chassis kit that uses a Slot.It inline pod.
https://www.professormotor.com/product-p/mb13500.htm
I bought one and can let you see it at practice. Slotting Plus also markets a Stainless steel and companion Aluminum chassis for the AllSlot; they are appx $15 and appear robust; Yes I know Ary does not favor them but they -or the MB Slot chassis- may be future alternatives to the SS&CF Spanish chassis we got in 2016 (which is now out of print and hard to replace).
http://www.professormotor.com/product-p/sp500001.htm
http://www.professormotor.com/product-p/sp500002.htm
"... get on your bad motor scooter and ride!"
Sammy with Montrose