What LED form factor is this?
Get the datasheet, and it should tell you exactly where the mounting holes are, how far the body extends, etc.  I wouldn't assume this is a "standard" package without checking the datasheets of other companies.  This may be only a common package within the product line of a single company.  Of course sometimes different companies create drop in replacements for their competitor's products, but you have to check yourself.  Even if one company claims to have a drop in replacement for another's product, I'd check the datasheet too be sure how equal the two parts really are, including mechanical issues.