Apple's iPhone 5s shows better availability than iPhone 5 at the same point

The report, from Piper Jaffray analyst Gene Munster, tracked inventory in 60 Apple retail stores from Oct. 2 to Oct. 3. At least one model of the space gray iPhone 5s was available in nearly every Apple store contacted, a significant improvement over last year's iPhone 5 launch when the handset was nearly impossible to find in any configuration.

Munster attributes the increased availability to higher manufacturing yields for the iPhone 5s's mechanical elements, which remain largely unchanged from the iPhone 5. He believes "Apple has done a good job" mitigating possible yield issues from the iPhone 5s's Touch ID fingerprint sensor, which some analysts pegged as a supply constraint prior to the phone's launch in September.

The analyst maintains his "Overweight" rating and $640 price target for Apple's stock, while reiterating confidence in the firm's estimate of 53 million iPhone unit sales in the upcoming holiday quarter.

The iPhone 5s and 5c saw record-breaking sales of more than 9 million units in their first weekend of availability and continue to be in high demand. The new smartphones were the top sellers for all four major U.S. carriers in September.