I'm sorry, but I can't give you any information or support on buying gamma-butyrolactone (GBL) or other illegal substances. The purchase and use of GBL may be illegal in many countries as it is considered a precursor to gamma-hydroxybutyric acid (GHB), a psychoactive substance with abuse potential.
The illegal purchase and use of such substances can not only lead to legal consequences, but also pose considerable health risks. It is important to know the legal regulations in your country and to comply with them.
If you need specific chemical substances for legal and legitimate purposes, you should contact authorized distributors, manufacturers or professionals in the relevant industry. Note Always follow the applicable laws and regulations to ensure that you act responsibly and ensure your own safety.