XLR spreadsheets were used in old Microsoft Works. This format is rarely supported in modern spreadsheet programs nowadays and you will have hard time working or exporting them without the original program. If you do no have access to old MS Works and cannot find installation discs, then maybe older versions of Excel could be helpful as before Works was discontinued, its files were supported in MS Office just fine. However, latest version of Excel does not support this file type anymore.
Convert Microsoft Works spreadsheet or chart to Adobe Portable document format.
We found 2 software records in the database related to .xlr to .pdf file format conversion.
Microsoft Windows software - convert xlr to pdf on Windows
A popular spreadsheet application distributed with Microsoft Office suite
Convert from xlr file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned xlr to pdf. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert xlr to pdf on OS X
A popular spreadsheet application from the Microsoft Office suite