I would look for another label or tag with heater specifications.
"Two toggle buttons" suggests two switches. One might be on/off, the other high/low. If you can not find a single dual switch, perhaps you can find two separate switches that will fit.
Suppose the heater was 1500 Watts, which would require 6.5 Amps at 230 Volts. Switch(s) rated for 10 Amps would be sufficient for up to 2300 Watts, if you can find some that fit.
Fred