Racing a Westerly
You should easily be able to measure your yachts sails and mast yourself. Just hoist some thin rope up a halyard and mark off with tape. Or hoist up a tape measure. At Royal Torbay YC we use the Limited Validity TCC IRC Certificate rather than the full IRC. Limited Validity should cost about £35 instead of £100. https://www.rorcrating.com/2012-rorc-rating-news/211-limited-validity-tcc-initiative-for-2013
The way to get an updated RYA PY Handicap is to follow the link below to Byron Software. http://www.byronsoftware.org.uk/bycn/
IRC is a measurement handicap and widely recognised as the most accurate, because it handicaps the vessel not the sailor.
PY as run by RYA, is a very useful system, but is an average of averages of averages etc. If there are a lot of your type of boat competing in handicap races it will be reasonably accurate, but if the reverse is true the accuracy reduces quickly (usually against).
The Byron Software was developed to artificially re-produce this and therefore increase accuracy for small classes and one offs.
Given the choice I would race IRC, as I like to know it is the closest (not perfect, but best) system.
At the end of the day it is the club members who decide which system they want to race under and therefore which systems the club uses. Voting with their feet (should that be keels?) is the best way.
Results Westerly Typhoon
Some of the results are published under the chapter Typhoon here on this site, please edit if you are a "typhoonist".