My 2 cents
First, there are a LOT of Upper Deck LeBron rookie cards that year, all I can find so far for the #53 card is around a $1-3 w/free shipping (edit--earlier link was wrong) without card holder or "Gem 10" grade
but to have a LeBron rookie regardless is nice.
Second, how nice of cards you want to get a young child depends on whether you look at the first set as an investment to protect carefully. It's not clear what condition the rest of the cards are in, and whether they are investment quality anyway. If you looked at cards like I did as a tyke, I didn't care that much about investment value as much as I wanted to TOUCH the cards, rifle through them, look at the stats, admire the design and colors, and just admire them in my hands, not in protective pages, so
Third: If you're buying relatively cheap cards like this (and admit it, 2-1/2 cents a card is pretty cheap no matter how you look at it: $19.99 + $5 shipping), you're not really worried if the 6 year old doesn't handle the cards really nicely (at least I wouldn't)--I just want them to enjoy it. I collected just about all of the cards listed here. I just gave some of these old cards to a teenager who got a kick out of seeing old cards, even if they weren't "mint", and some were stars.
If we find out the other cards they're selling tonight are in top shape, then maybe being a little more cautious is worth it. However, it's awfully tempting to get some as a gift for that teenager and/or for myself (because this does go back to my childhood years) because I probably won't worry about how carefully I take care of them (the cases, the binders, the worrying over caring for them, the gimmicky cards, etc.). I still like the feel of looking at cards in my hands, so once every few years, I'll just buy a pack to get the feel again. This offer would have been perfect for me growing up, but I'm not sure how today's kids are.
Hope this helps. Bye.