Fortunately for me, I was able to show her the free pattern by Alison Hansel, which met her requirements perfectly - even to having the beautifully soft and luxurious yarn used in the pattern, Jo Sharp Silk Road Aran Tweed, in a gorgeous shade of a deep, dark maroon with flecky bits that looks great with jeans (colour now discontinued, sorry).
I made the size Child L/Adult Small, using 9 balls of the main colour, and 1 for contrast, and found it a very easy and quick knit.
The pattern does not include an R initial, but it was not difficult to adapt the included H.
I used a knitting graph paper from this site to make the R
I knit this in, using intarsia, rather than doing duplicate stitch afterwards, and I also adapted the pattern to knit the bottom in the round up to the armscyes, and the sleeves in the round on double pointed needles. This meant that I had to break off the yarn after each line of the initial intil the front/back division, but as this is only a 1/3 or so of the initial the weaving in was not too painful afterwards.
There is an extra few lines of the contrast yarn in my version at the neck, as this idea took my fancy as I was finishing off the jumper.
The only other thing I can say about this jumper is that it is in terrible danger of wearing out in a single season due to overuse!