Indexing with alternate criteria

I need further assistance with the problem of indexing in prices into an auto-fill form based on either a standard or discounted cost. I have tried
several formulas and none seem to give me the answer I am looking for. I have attached a sample workbook. I appreciate the assistance. Thanks.

<Why haven't you a Price file totally independent of the Order form? Your format is far from ideal, not least because the VLOOKUP reference for the Part No: (and other data) - it is "hard-coded">

The price file is actually on a separate tab and is hidden along with some other tabs that weren't pertinent to the posting.
The formula you provided returns the part 2 number. It doesn't address the original question.

=VLOOKUP($C$3,'PART ORDER LOG'!$A:$BJ,15,FALSE)returns "NC-LD80-28". I need a formula that will return either the Standard Price or Discounted price based on whether
Column F on the form is an "S" or a "D".

I'm a bit confused by your sheet. It seems like you probably just need an IF() clause to choose between 13, 18, 23 in your existing formula. But I'm not sure what it should actually be since you say you are choosing between two input values (S and D) but have 3 options as the output (13, 18, 23).

I'd also make the same point as John, that hard-coding the column number is not a very robust way of doing things in a big sheet like this. If a column gets added somewhere you need to change a bunch of numbers. I'd suggest either using a MATCH to get the column reference or using XLOOKUP instead of VLOOKUP.

Oh actually think I get it now, each row adds 5 columns to the right but as well as that you are choosing between PR and DP.

In which case try something like this in D15:

=VLOOKUP($C$3,'PART ORDER LOG'!$A:$BJ,IF(F15="S",13,IF(F15="D",14))+5*(ROW(D15)-ROW($D$15)),FALSE)

This formula worked perfectly. Thank you so much.