1991 Transmission problem

hi i was hoping someone could help me out on this.
i have a 1991 4runner 4x4 V6 3.0 litre.
i have been having problems with i guess the transmission as it is not engagin in drive or reverse. the problem started with the car soley not moving in reverse, i drained the transmission fluid and it was distintcly burnt and watery so i removed the drain pan and filters and cleaned them - there was metal shavings in the filter and then sealed everything and refilled with fresh fluid and a thickening seal agent.
it now is very difficult for the car to drive and reverse does not work at all. i am wondering if the injectors or filters could be blocked or if the gears are actually gone and what options does this leave me with?
if someone has a transmission for sale i would be very interested and any advice would be much appreciated
thanks

I,m sorry to say...but it sounds like toast to me..probably needs a rebuild. $1000-$3000
best of luck