not sure which ones you are looking at, but you can get the holders at walmart and lowes for $5 or less. I wouldn't order online as the cost plus shipping will probably be more than what they are worth. $3.99 at Lowes.
I ordered 4 of these from wally-world a year or so back and shipped site-to-store...they work OK...it says it can handle up to 4lb bird, I've done over 5lb, but had to be careful so they didn't tip over on their side/back...price was $5.00 then...took quite a jump now, I see.
I must have done 50 birds or so and have never used anything but a beer can. Why do you need a rack? I usually do 2 birds at one time and run a couple of bamboo skewers thru the two birds to have them help each other balance - what does the rack do for ya?
I have the same thing and love them and they also have little spikes where you can shove a potato or anything like that into is as well so you can smoke them. You can do them without the holder its just nice having the double one and you grab the rack and go inside without any issues and you don't have to be careful as they can't tip over. Especially if you are a wee bit tipsy yourself. hehe
I guess it is just me but I dont need another device to clean - I did try one that had a grease tray at the bottom one time but it got too full and overflowed so I had more clean up than normal - I use a 16 oz can most of the time so I can drink more before putting them in and with the skewers mine have never fallen - just lucky I guess