I am not sure there is an alternative. PZL only do the 80mm type.
Croft

At 08:58 21 November 2011, Ventus2NZ wrote:
I have just had my Winter 57mm altimeter fail it's instrument check.
From what I can ascertain, this is not all that uncommon. Does anyone
have any ideas or suggestions of a suitable 2-1/4" alternative.