Lookup value from closed workbook based on 2 criteria function

[cornfedtm]

I'm, in a way, attempting to replicate the popular StockQuotes function that is useless now that Yahoo took down the ichart site. I have saved excel files with historical price data named by the stock symbol (ex: BABA.xls, MSFT.xls). Based on Symbol and Date, I've been trying to use VLOOKUP with the Table Array field housing the file path and filename and search location. I have to change the file name manually for each symbol however. Is there a way to have the formula update the file name automatically when it is changed? I'm not familiar enough with VBA to attempt a function, although ideas would be much appreciated.
The price data files have 5 columns (Date, Open, High, Low, Close). Using Date row and Close column to lookup the closing price. The price data files are closed during the lookup.

 

[cornfedtm]

Below are a couple of examples of the current formula and table layout I'm using:

=VLOOKUP(C$2,'E:\Dropbox\Pub\CSI Stock File Downloads\[BABA.XLS]Sheet1'!$A$1:$E$65536,5,FALSE)*$B3
=VLOOKUP(C$2,'E:\Dropbox\Pub\CSI Stock File Downloads\[GLD.XLS]Sheet1'!$A$1:$E$65536,5,FALSE)*$B4

Stock	Shares	8/18/2015	8/25/2015	11/4/2015	2/11/2016	4/20/2016
BABA	200	$ 14,776.00	$ 13,714.00	$ 17,080.00	$ 12,114.00	$ 16,242.00
GLD	100	$ 10,711.00	$ 10,916.00	$ 10,597.00	$ 11,906.00	$ 11,897.00

<colgroup><col style="width:48pt" width="64"> <col style="mso-width-source:userset;mso-width-alt:3437;width:71pt" width="94"> <col style="mso-width-source:userset;mso-width-alt:4169;width:86pt" width="114"> <col style="mso-width-source:userset;mso-width-alt:3657; width:75pt" width="100" span="3"> <col style="mso-width-source:userset;mso-width-alt:3218;width:66pt" width="88"> </colgroup><tbody>
</tbody>

When symbols are changed in column A, is there a way for the file name in the formula to update automatically, rather than manually. Takes a lot of time the longer the list gets. Thanks.