I have an opportunity to purchase a Springfield Armory 1903 that's in the serial # range of the improperly heat treated receivers.  It has been arsenal rebarreled twice, and I presume Proofed 3-times (original bbl + the two rebarrels).  Given this, is there any issue with the receiver at this point?

No issue and there was never really any issue in the first place as these were issued through WWII after refurb. Theres also been numerous documents released from Hatcher himself and US Ordnance stating the fact that these rifles are safe and should be issued regardless of serial number.

The real issue of them blowing up came down to really faulty ammo, particularly from Winchester who loaded very hot ammo and their consistency at the factory varied greatly.

Some info in this recent thread, too:

https://www.ar15.com/forums/general/Just-got-a-1903-school-me/5-2711247/

I have a low number 1903 I have no reservations about shooting. I checked the headspace, and shoot only newer quality ammo.

As others commented, it more of an issue with bad casing giving out, and pressurizing the receiver blowing it out. I don't recall seeing any where the bolt moved back or stuff like that.

My Dad's brothers, some of whom were in the Service then, suggested (and  Col. Brophy seems to confirm) that the total number of burst '03s from bad heat treat never exceeded about four per cent, it was just that a couple of the accidents happened in very public circumstances, and you guys know better than most how well rumors propagate. The Army had to do something to restore the Doughboy's faith in his rifle, and after all the new heat treatment was a real, measurable improvement. I wish even one or two of my uncles or Dad were still around, I have so many questions-- Dad test drove the first Bantam Jeep prototypes through the impact ranges at Camp Holabird to see what broke, and later was James Jabara's 1/Sgt--

ETA: Some years ago I had the honor of refurbishing the local American Legion post's '03s, eight four-digit rifles sent from Redstone Arsenal to the Post in 1947. Lots of pre-1906 parts, modded sights, all kinds of fun, and I got an "Old Rifle Fix-It Award" and a load of good will from the Post. There was so much jacket metal in their bores that if there had been any problems they would have let go by 1922. It is hard for me at this point to decide whether the Army's blanket ban on the use of the low-number rifles was based on insufficient info, or (more likely in my mind) a CYA maneuver on part of someone in Ordnance.

Did I mention I love 1903s? The lady who is now my wife, the first Christmas we were together (1998), gave me a 1902-dated Phillippine Constabulary Krag carbine-- I knew right then she was My Kind of Woman!

True.

I recall a few of the rebarrelled and put in storage until sold by the CMP had short chambers.  They got rebarrelled and no one obviously checked the headspace and used the pull through reamer on them.  Guys had CMP buys that wouldn’t chamber a round or accept a go gage.   Not many guns but a few.  CMP took care of them.  

I have a pull through 7.62 nato reamer but not a .30-06 one.