Alternative parts for Rev D. Need assistance in sourcing and confirmation.

[aries1470]

Hi,
As I am awaiting for the boards to arrive, I wanted to confirm some alternate parts, as I am unable to source, or if I can, I need to purchase a huge quantity.

I will start with the following:

1. Q4 & Q5: J113. What is their purpuse, and are they critical? I can substitute with the following:
   • NTE312 or MPF102 or NTE457. I am leaning towards the MPF102 , then NTE312 (closer to spec's with J113) then NTE457 (due to pricing in that order). Does 50mA actually get used as per the J113 specs? or the whole voltage, since we are running ±5 V. The NTE312, I just flip it around from GSD to DSG so it will be facing the other way, while the MPF102 drops in directly, but is ±25V 10mA.
   
   
2. U6 & U7: MC14538BCP. I can only source the following:
   • HEF4538B and CD4538BC. Having looked at the pdf files, can someone confirm if pins: 1&15 are used? Since for the On Semi (Motorola) part, they are Vss and mentions to connect them together, while for all other companies, they are:Pin1: T1A and PIN15: T1B. Else, they are exactly the same part. Can this be confirmed.
   
   
3. Coil Wire: I will be using Kynar 30AWG Wire Wrap Wire Silver Plated (only because I have it on hand). I have become confused from reading way to many posts. In short, Can it be used without any issues? or is it better to get any of the following wires:
   • 0.25mm Enamelled Copper Winding Wire
   • 0.4mm Enamelled Copper Winding Wire 28SWG
   • would I need to do anything to the enamelled wire or just use it straight and then shield.
   
   
4. For coild shielding, would this suffice, will I need shielding? copper tape and will be using Temflex Black Electrical Tape as the insulating material between the spool and the copper tape, would this work if I have understood the assembly isntructions correctly, or I can use kitchen alufoil ofcourse
5. Replacing the LT1054 with TC962, I don't see an issue excpet for 20 mA difference in output. I don't see the whole circuit using that much current, but I can be wrong, as I have not worked with coils previously.
6. D10: Replace MUR460 with UF3005. This is also 600V but 3A. Is there a reason it needs to be 4A? This is what I have handy.
7. R6: 100K Multi Turn. Does it need to be of a certain wattage? or is a 1/8W or ¼W or ½W?
8. Why is the IRF740 chosen? Can another part be used? What spec's are we looking at that are needed?

This is for the stock version, once I have it up and running, then I will do mod's, but I want to confirm if these items will be okay.

Sorry for the lots of questions, I just want to have everything ready for when the pcb's arrive, to "hit the road running" as they say

Thank you kindly for your replies.