It really depends on your quality system.
If you have written the method as " Product xyz from supplier abc ", then your quality people would probably expect a deviation to be issued if the supplier or grade is changed.
If you have specified ACS or Pharmacopoeia grade, you can use those grades from any firms on your " approved supplier" list.
The most common solution I've encountered is to specify " Solvent - HPLC Grade - product xyz from supplier abc, or equivalent ".
Sometimes terms like " Product xyz from supplier abc has been found to be suitable ", are used, but auditors can ask what that really means.
The main issue is to ensure that you have a documented comparison of the performance and/or specifications of the two products, and that both suppliers are on your approved suppliers list, and thus potentially subject to quality audits.
Please keep having fun.
Bruce Hamilton