It may be possible to covert the rear to discs, which will be much easier to service in the future.
Even the cheapest DOT3 at Walmart is fine as long as you change it regularly (every few years, or every time you replace the pads and/or rotors), but more premium brake fluids with their higher boiling points give you a little extra margin of safety and performance. The LV fluids out there also make the ABS work better, especially when it's cold.
Castrol brake fluid (formerly called LMA) is supposed to absorb moisture more slowly, which of course will give you longer life between fluid changes. Hard to find in stores (it used to be more readily available but no more), but easy to find online. Lower viscosity than standard brake fluids, but not quite an LV. Part number 12614. Dry boiling point 509, wet 329.
Valvoline brake fluid is usually a decent price and widely available. It is labeled as both DOT 3 and DOT 4.
You can also use DOT 5.1 NON-silicone (but NOT DOT 5 silicone) Wagner Severe Duty is the cheapest DOT 5.1 out there, part number FC133301. Dry boiling point 500, wet 356.
Speed bleeders are awesome