I would suggest having a careful think about what you want. Your question is really like asking "How long is a piece of string?".
1) Find the Ixx and Iyy dimensions for your proposed mast. Most mast "makers" will be able to work
these out for you. Make a note as every time you talk to someone they will want to know these numbers. Basically they indicate how stiff the mast is to be.
2) Do a sketch of what you want. On your sketch show :-
i) Where each piece of fixed rigging
attaches to the mast.
ii) What running rigging
iii) All key dimensions. Ask the mast makers what they need.
iv) All parts
that are to attach to the mast. Include steaming, masthead and spreader lights, together with any VHF
aerials etc. Don't forget the hardware
that takes the wire from these inside the boat. If you have special requirements for spinnaker/whisker poles or sail track make a note. Jiffy reefing would also be marked.
v) How the boom is to be arranged. This includes any jiffy reefing and bolt rope/sail track and where and how the mainsheet is attached.
Try to get your sketch into digital form (JPEG?) so you can email
it to mastmakers/riggers/sailmakers etc.
3) When discussing this with the mast makers ask if they can do the installation/rigging. If they can't then you will need a local rigger.
4) This is a good time to decide if you want a sail bag or roller reefing. Discussion with a sailmaker
may be indicated.