Pictures would be a great help.
What you have is a KAR 98K, made by Waffenfabrik Brunn, which we know today as CZ Brno. They were quality rifles.
You have a partial mismatch, which is not uncommon. No big deal. These are not highly valuable even when "perfect". Your value is not it's worth as money either... you would be a fool to ever sell it.
One of his friends probably gave it to him as a favor, these were very common at the end of WW-II and had little commercial value at the time. A friend might hand one over to a friend as a gift without stretching belief.
Let's see some pics and then we can probably advise what the best "restoration" is. The bottom line is that you might be replacing wood, and then not doing anything else. Never drill a hole... etc. Bottom line is that if you do not know what you are doing, do nothing. If you do know what you are doing, write down your plans and wait a year and then go back and review them and see if you still feel the same way. Avoid the temptation to do "something".
The front sight hoods are removable sheet metal. Presence or lack means nothing.