I looked for flights, and I found plenty of nonstop ones to Albuquerque and Wichita, alongside plenty with stopovers in Houston, Atlanta, Denver, and Chicago.
For Carbondale, the nearest airport is in Cape Girardeau, MO, about 45 mi away. The nearest town with an easily-accessible airport is East St. Louis IL, near St. Louis's airport.
I used orbitz.com to find estimates of travel times and costs, and for Chicago and Denver, both cost about $100 with travel times 2h 30m and 2h, both nonstop.
I then considered other big Texas cities. Austin - Denver: 2h 15m, Houston - Denver: 2h 30m.
Lessons from Before Roe: Will Past be Prologue? | Guttmacher Institute has a discussion of abortion tourism.
When the UK liberalized its abortion law in 1967, it became a big destination for abortion tourism, with 600 American women going their in the last 3 months of 1969. By 1970, package deals were advertised in the popular media, deals including not only the procedure itself, but also airfare, passports, vaccination, transport to and from the airport, and lodging and meals for four days.
In 1970, four states, AK, HI, NY, and WA repealed antiabortion laws, generally allowing abortion on request before fetal viability. AK, HI, and WA had a 30-day residency requirement, NY didn't, and it became a popular destination for abortion tourists.
In the year before Roe vs. Wade, just over 100,000 women went to New York City to get abortions. Some 50,000 traveled more than 500 miles, 7,000 more than 1,000 miles, and 250 more than 2,000 miles, from places like AZ, ID, and NV.
The expense of going to NYC, staying there, and getting the abortion had this consequence. "While eight in 10 nonresidents obtaining abortions in the city between July 1971 and July 1972 were white, seven in 10 city residents who underwent the procedure during that time were nonwhite."
A further consequence was delay in getting the abortion. In 1972, no more than 10% of NYC residents got an abortion after the 12th week of pregnancy, while 23% of women from nonneighboring states did so.
There was also the problem of followup in case of complications, because by the time such things happen, the woman may already be home, and a long way from the place where she got her abortion.