I wouldn't replace those with modern regulators. Although these analog regulators generate more heat, these regulators have really good over-current (overload) and over temperature protection. The modern switching regulator replacements are not as good in this respect and have possible failure modes that can result in their output voltage equaling their input voltage. Personally I don't trust them, and I would never mutilate a historic board like this by fitting modern switching regulators to it. Also, it is somewhat anachronistic and just doesn't look right. A little like fitting Fiat Bambina car doors to an 18th century French polished Walnut cabinet.
The best you can do with these vintage regulators is to make sure their input voltage for the 5V regulators are kept to the range of 7.5V to 8V. It pays to run your computer by a line Variac to ensure this is the case. This way there is minimal heat dissipation in these analog regulators.
