Hello Rudi,
Of moet ik zeggen, hallo Rudi! ?!
Zo dat de anderen op de forum mijn antwoord zullen verstaan zal ik wat volgt toch schrijven in het Engels …
Up until about a week ago (17 January to be precise), the RNLI archives in Poole (**LINK**) had a mail order service for life boat plans from their collection, which I am reasonably sure included plans for the Arun class that would have been of interest to you. Alas, they now say in their FAQ that this has been put completely on ice until sometime after the Summer, for a complete review and overhaul of these activitites.
More specifically they say:
"From 17 January the RNLI will be pausing its mail order service, including the online shop. This is so the charity can review its processes and suppliers to ensure the service provided is the best it can be. Therefore, this product is no longer available to order.
The RNLI is working on an interim solution and hopes to have products back online for autumn 2017.
If you have any questions about a current order please contact our Supporter Care team on 0300 300 9994 (UK) or +441202 663234 (Non-UK)."
You can always try your luck, and get in touch with them to find out about the "interim solution"; perhaps it would be possible to get copies of plans if one were to go to Poole and visit their archives — somehting that might be worthwhile anyay, if one were thinking about building a model of a lifeboat …
Good luck and good hunting!
Mattias