My Hitachi DVD player, Model DV-P735u, won't play a DVD, but will still play
CD's.

No doubt due to the fact that the player was likely OEMed by Samsung. They
just don't make decent DVD players.

But, I was wondering
where I could buy the pickup, and attempt to change it myself.

A parts supplier, like MCM, Dalbani, or Digi-Key, to name a few.

Or, trying calling a local electronics shop to place an order for a part.

You will need the item number of the part, which may sometimes only be listed
in the service manual for the player.

Also, is it even worth the cost
or effort to repair, even by myself?



Samsung usually calibrates their pickups at the factory, which puts one aspect
in the repair out of the way.

You will need a soldering iron to undo the solder short on the new pickup.
This short is put there by the factory to protect the internal pickup
electronics (laser diode, photosensor) from electrostatic discharge damage.
You must remove it prior to installation to allow the pickup to work and to
prevent damage to the player. - Reinhart