Yep, replacement engine is the go here, for sure.
From that quote, the valve guides are worn and the valves damaged, the crank big end would need to be ground to fit that undersize conrod, and the bore and piston are damaged. What all that adds up to is, 'not economically repairable'. Even as a DIY job...
BTW the part number for the conrod is just 390459; the description is 'Rod Assy. - Connecting (.020" undersize)'.
The Parts List is here [PDF download]
http://bsintek.basco.com/MDEXResultsPages/PDFDisplayPage.aspx?fileName=Z6nlxAVJ1DajI