Is N-methylimidazole an unusual solvent, or are there more common substitutes for it? I want to test a process that was documented in the literature using N-methylimidazole.

I am not doing academic research, but rather testing a documented reaction for application to an industrial process, so I don't believe I need lab-grade chemicals.

When I look for this solvent online I can only find lab suppliers (e.g., Matrix Scientific, Acros Organics, Alfa Aeser) selling tiny quantities at very high prices.

Is there something unique to this chemical as a "donor solvent" that is not reproduced by any more common or inexpensive solvent?  I have seen it mentioned frequently in organic chemistry papers, but since I can't find industrial suppliers I assume it's peculiar to research.

The application I'm interested in is chemical stripping of lead using Rauchfuss's Elixir, which consists of sulfur as an oxidant and a donor solvent.  I haven't been able to learn why they used methylimidazole as the solvent in the study.  Obviously I would prefer one more widely and/or cheaply available.
http://www.chemicalbook.com/ChemicalProductProperty_EN_CB1316726.htm 
http://www.lookchem.com/cas-616/616-47-7.html 
http://www.guidechem.com/cas-616/616-47-7.html  2000 RMB = $(USD)320  
http://ahjinao.en.alibaba.com/product/595605676-209523668/Time_honored_Supplier_of_N_Methylimidazole_CAS_No_616_47_7_.html 
http://www.alibaba.com/countrysearch/CN/n--methylimidazole-supplier.html 
http://www.buyersguidechem.com/chemical_supplier/N-Methylimidazole.php 

Info and suppliers,  Note that a Chinese contract is often not the legal or philosophical equivalent of a Western contract.