First, you might want to add a column for supplier name (or ID) so you will be able to tell where you can get the lowest price.
The easiest way to get what you want would be to write a macro that
1. Copies the table to a new worksheet,
2. Sorts it by part number then price ascending
3. Deletes every row where the previous row has the same part number.
You can get a good start on your macro by recording the first two steps. When you select the range to copy and sort include as many empty rows at the bottom as you are likely to need for some time.
Assuming the part number is in column A, the code for the third step would look like:
iRow = [second row number]
Do While Cells(iRow, 1).Text > ""
If Cells(iRow, 1) = Cells(iRow - 1, 1) Then
Rows(iRow).delete
Else
iRow = iRow + 1
End If
Loop
Note that you increase iRow by one only if you do not delete the row.