I used a table of RYA PY values from their website some time ago for cruisers and the Irish Sailing Association ECHO handicap (time correction) values and after eliminating outliers came up with the following linear regression formula
(1000/PY)=1.572(ECHO)-0.4126 with an R^2=0.769
Using this formula for the Galion 22 with and ECHO 0f 0.805 gives a predicted PY of 1172. The smallR^2 value indicated a poor linear correlation but using non linear regression doesn't do much better. I didn't force the regression line to go though the origin which it should do.