So you have $600 and swapping the tranny will be around $2k.
A rebuilt 350 like yours should get around $750+
Whatever wheels and tires you have on it 500
The 1 ton rear 300
The body and frame 1000+
The x fer case 250
-----------------------------------------------
$2800
+ 2000 - what you are getting ready to dump in it ---------
$4800
+ 600 - you already have ----------
$5400
That will buy you a heck of an older tow rig.
It might be 2wd, it might not be a BEAST, but it will do the job you have been begging yours to do without fail.
Or, we could all just copy and paste Bigwoody's post above and keep it on the clipboard for the next thread that pops up.