just fix the drum brakes.
there is nothing wrong with having drums.
they have been around for over 100 years.
disk brakes are easy to work on and that is about it.
take them all the way apart, clean every thing up.
don't use grease. use oil, sticky stuff like for lubing chains.
make sure the adjusters are in right and loose.
make sure all the little factory plugs are replaced.

I don't want a pissing match over disk vs drum..
I am just saying that a drum brake works well if maintained.

some things that you don't want to do.. found alot of this redoing my wifes rear brakes.

make sure all springs are in correct orientation.
do not use large amounts of grease.
do not put grease where it is not supposed to be. look at the manual.

her's the adjuster on one side was backwards. they were both locked (very hard to turn) from the grease and dust in them.
one side had a spring in the wrong place.
the shoes were burned so bad that they just fell off the backing because the PO adjusted them to the point that they must have been about locked up. or drove with the e brake on for a long time.... the backing clips were bent and binding.
after I rebuilt them and put everything back the way it was supposed to be they work great.
some of the friction surfaces DO NOT get grease as they don't move much like the e brake levers.

drum brakes have or store alot of heat and dust, keep that in mind when rebuilding them if you don't have the manual to follow.

not to pick on you personally but I am or have been in this (argument) many times.
disk brakes are better on alot of levels. but drums work.
don't give me that salt belt stuff. I live there. that is where all the little factory plugs are pure gold. do put a bit of grease on them to help sealing.
with brakes grease, oil, are good in the right places and really bad in the wrong places.

drums have been, and still are on all kinds of cars, trucks.
I would not be able to even guess at how long they have been around 200 years??. if they didn't work, don't you think they would have changed them a LONG time ago.

I recently saw a drum brake that was a 100 years old stop a rotating mass of over 8000 pounds at 80 rpm in about 3/4 of a revolution. it was about 20 inches across about 4 inches wide. had a leather pad that went around it backed by steel. I was so impressed that I asked the owner (it was a big generator from home stake mine) he said, and I believe him that it was the original and had not been replaced.

I digress.. sorry.
but in my opinion it is not worth the money to go to disks.
drums are complicated compared to disk brakes. but set up right they work well.