The definition under current market value 221.2 has three options, which are separated by an "or". If this stock is publicly traded, I would use (i) and if not, I would use (ii) rather than (iii).
If you refer to 221.123, it indicates that the contemporaneous payment of capital gains tax would be purpose credit when extended by a plan lender. Without other guidance, I would have to opine that the same would be applicable to a non-plan lender.
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