On my Model 26 RRAs, the early GB "Hiduminium" brakes will accomodate 27 x 1 1/4, 26 x 1 1/4 & 26 x 1 3/8 wheelsets.
I don't know if your Lenton has similar geometry to the RRA though, but the pad adjustment slots on these brakes are very long.
I imagine those particular decals were pretty unique and a small production run, love the little snowflakes on the seat tube.
Perhaps you could make some scans and get a reasonable price from one of the smaller decal makers?
For example https://www.isaydingdong.co.uk/custom-jobs.html
I see that you've already found the most comprehensive website i.e. "On the Drops".
The Raleigh catalogues usually stated the posh "new" eye-catching colours for a particular year - but what they didn't always say is that most models were also available to order in the "standard" range of...
Hi. looking for a good vintage Weinmann 26" x 1¼" 40 spoke alloy rim, style as per the attached pic. They were made dimpled or non-dimpled - I'll take either.
Ta.