Most transmissions/transaxles aren't fond of selecting second until they are warm. It's just a trait of early synchromesh designs. When the oil is cold, the 1-2 change has a definite two steps. First you stop the synchro, then the gear. It's so slow that gear has the time to change speed after the synchro pressure is reduced. Thus it grinds. You need to run the car easy for the first few miles/kilos and keep the revs sedate until the gear oil warms up. Some cars are so bad you actually bypass second until it warms up. Synthetic gear oils help a lot but are not a perfect cure.
I can't tell for sure from your photos but the synchro collar doesn't look that bad to me. Some rounding of the "teeth" is not unusual and doesn't impair function. Test your synchros. Push and twist the synchro against its angled seat on the gear. It should tighten and lock, and not go all the way on. As the synchro wears, it travels further up the angled seat until it "bottoms" without gripping.
Lastly, I hate to keep repeating this, but NG transaxles are physically larger and have physically larger parts. They do not interchanged with the 336/352/365/395 series. Best to find another 395 transaxle for parts. Even then there are different versions and some parts may not interchange.