Where in God's name did you find this info?
Thank you for the compliment. This information is readily available but sometimes takes a little hunting, I just happen to love research as much as the build so have collected a list of websites and books over the years. The Steel scantlings are in his book
The Elements and Practice of Naval Architecture, (pricey and hard to find at times) W.E. May's book
The Boats of Men of War, and
Scantlings of Royal Navy Ships by yours truly, the latter of which has scantlings for all sizes of British ships, not just boats, from the Establishments,
The Shipbuilder's Repository 1788 and Steel's
The Elements and Practice of Naval Architecture,
I downloaded the 800 high resolution RMG drawings from the Wikicommons site and categorized them in folders by number of guns, and of course there are many thousands in low resolution on the RMG site itself that are to scale. Even the low res plans are often good enough to use to measure things like the thwarts.
I also started collecting contracts of ships, some of which I have transcribed, many more that are still in their original form. There are a lot of contracts on the RMG site and I was VERY fortunate to receive others from a fellow research enthusiast from other sources. If I had enough years I would love to finish all the transcriptions and do a book of contracts.
After market items can be expensive but the producer needs to make a profit or there would be none for us to use. There are alternatives at times. For example, if you want highly detailed accurate cannon of the right size and appropriate pattern, and are OK with printed versus metal, they can be found for a low price. I have never paid over US$1 each, including domestic shipping for 1:64 scale guns.
Allan