LeBron James has many valuable basketball cards, but here is a list of his top 10 most valuable basketball cards and their estimated value as of my knowledge cutoff in September 2021:

2003-04 Upper Deck Exquisite Collection Rookie Patch Autograph #78, valued at $5,000 - $1,000,000+ depending on the specific card and its condition.

2003-04 Topps Chrome Refractor Rookie Card #111, valued at $10,000 - $150,000 depending on the specific card and its condition.

2003-04 Ultimate Collection Ultimate Logos Signature #UL-LJ, valued at $50,000 - $200,000+ depending on the specific card and its condition.

2003-04 Upper Deck Ultimate Collection Ultimate Signatures #USLJ, valued at $10,000 - $100,000+ depending on the specific card and its condition.

2003-04 Upper Deck Ultimate Collection Ultimate Rookie Autograph #127, valued at $5,000 - $100,000+ depending on the specific card and its condition.

2003-04 SP Signature Edition Autographs #ASLJ, valued at $5,000 - $50,000+ depending on the specific card and its condition.

2003-04 Bowman Chrome Gold Refractor Rookie Card #123, valued at $50,000 - $100,000+ depending on the specific card and its condition.

2003-04 Topps Rookie Matrix Autographs #RM-LJ, valued at $10,000 - $50,000+ depending on the specific card and its condition.

2003-04 Upper Deck Finite HG Signatures Gold #LJ, valued at $5,000 - $50,000+ depending on the specific card and its condition.

2003-04 SP Game Used Significance Autographs #LJ, valued at $5,000 - $30,000+ depending on the specific card and its condition.

Please note that the prices listed here are just estimates and the actual value of the cards may vary based on the condition and other factors. It's also worth noting that the market for collectible cards can be volatile and prices can fluctuate significantly over time.