If the first gear synchronizer is bad, they are $411 (Jan 2025 price) at amayama. Makes looking at a new transmission with zero wear more of an idea. Kurt's source of H55 (and the H55 tcase combo) is a great drop in for US owners and cheaper than Toyota proper. Toyota has NEW R151's in the US system @ $1900 +/- for those who use that transmission behind a HZ/HD/HDFT/HDFTE (yes, they fit). The H152 is also a US part requiring a couple overseas parts (and bellhousing) to mate to HZ/HD/HDFT/HDFTE for around $2500 transmission plus parts.
So buying a used H55, R151, or H150/151 that needs any internal work needs to be well below the $1,000 price. In my mind the H42 (and H41 fad) are a dead issue and those transmissions should be scrap.
Transmission are not hard (just understand double engagement) and just make sure things line up and move easily as needed and follow FSM. Just don't get in too deep with parts costs.
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