This is a very brandable name. There is a cable used in audio recording called an 'XLR cable' (16.3Million Google results for 'XLR'), and the domain XLRO could stand for 'XLR Outlet', 'XLR Ordering', etc. I would look to get $1xx to low $5xx for it, and for an end user over $1,xxx.
I can't say much about the three-character .com, though. Sorry, but they are not my specialty.
All the best,