extract a string with a column

Hi

I have a column in my dataset that looks like the below. What I want to do is create a new column that extracts the R & L number sequence. For example on the first rows it would look like R1050819, second row L2050819. Ive done the split by delimiter which works ok but its a bit messy. Looking for a way to look for the L or R within the string and return the number as above.

Thanks in advance all!

Natasha 

Non Stock Purchase - X3744298 L2120819 3 X 20 2 X 40 [X3744298 L2120819 3 X 20 2 X 4]
Non Stock Purchase - X3744658 R1130819 6 X 20 16 X 40 [X3744658 R1130819 6 X 20 16 X]
Non Stock Purchase - X3744508 L1130819 14 X 20 8 X 40 [X3744508 L1130819 14 X 20 8 X]
Non Stock Purchase - X3744820 L2130819 1 X 40 [X3744820 L2130819 1 X 40]
Non Stock Purchase - X3743991 L1120819 15 X 40 [X3743991 L1120819 15 X 40]