Teitl clawr = Cover title.
OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
Adeiladau o ddiddordeb pensaerniol neu hanesyddol arbennig : Llanrug, Gwynedd (part). Published by Cadw in 2004. Publication and catalogue information, links to buy online and reader comments.
obnb.uk is a Good Stuff website.