Sort a listview but not alphabetically

Hello all,
I'm working with a listview. I need to sort the listview in this order. (These are names of data types and they are stored in one of the listview's columns)

BLKD
DBLE
BLKR
REAL
BLI4
INT4
BLI2
INT2
BLI1
INT1
BLL1
LOG1

As you can see, they are not alphabetical. There are approx. 20,000 to 30,000 items in the listview, so you can understand my need for an efficient algorithm.

I've considered using an enumeration, but apparently REAL is a keyword in VB.

Help greatly appreciated.

Cedric

add a number before your text:
eg.
0001_BLKD
0002_DBLE
...