The list of minimum required instrumentation will be in a document called the TCDS (Type Certificate Data Sheet). I'm afraid that I don't have a copy, but the LAME who looks after the aircraft might. Failing that, ring the local CAA office.
That's the legalities, my opinion would be not to get airborne in a medium performance light a/c without a compass (and I'm pretty sure it will be on the MMEL anyway) but you do need to check.
A copy of the MMEL might also be in the POH?
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