Does anybody else in the U.K. have trouble finding stocks of time-delayed RCDs?

Many of the local suppliers in my area either do not carry them as regular items, or never seem to have any in stocks.

Given the modern trend toward split-load boards and considering that we're a predominantly rural area with TT systems by the thousand, it seems rather odd, as there must be quite a call for them.

What's also curious is that many of the national mail-order suppliers don't seem to carry them as standard stock either.

How is it in your area?