My firsthand knowledge is almost as thin as my hair on this one, all I have to offer is "book larnin'"!

In "The Master Photographer's Toning Book", Tim Rudman tested various papers in gold toner. Ilford MGWT gave the strongest blue response of those tested, MG IV only gave a small colour shift.

There might be another (much cheaper) option, depending on what you're looking for... In the same book he tested Speedibrews Porcelain Blue toner, which is a two-bath bleach-and-tone arrangement. He describes it as "a joy to use" and waxes fairly lyrical (for him!) on the degree of control available by varying both the bleaching and toning stages.

As I say, it's only "book larnin'" but I hope it is of some use.

All the best,

Frank