Let me embellish a little on bleach and redevelopment. A suitable bleach will be a teaspoonful or so of potassium fericyanide, which you probably have on hand, and a teaspoon or so of table salt in a pint of water. The redeveloper can be as simple as 1/4 teaspoon of hydroquinone and 1 teaspoon of sodium carbonate in a pint of water. I have just tested these recipes, so I know they work. Bleach the negative until the image is translucent. Wash but do not fix. Dissolve the carbonate and add the hydroquinone just before redeveloping. Do not be alarmed by the sudden and intense color. 10 minutes at 70 degrees will be bountifully sufficient. Do this in room light. The negative must be exposed. The stain image will add considerable contrast to prints on graded paper and on VC paper with contrast-increasing filtering. There will be no increase in grain or loss of acuity.