French OakPLUS chips,  a smaller  chip  MEDIUM toast  4 ounce

Innerstave French Medium Toast provides complex, pleasantly mild and delicate toasted oak characters and aromas of vanilla, caramel, chocolate, hazelnut, oatmeal with honey, graham cracker, with a touch of cinnamon and nutmeg. The flavors provide sweetness, creaminess and roundness to the mouth feel with a lingering non-aggressive toast character.

French OakPlus Chips take 8 weeks for full extraction but 5-6 weeks should be sufficient.  Due to the length of time required for extraction, add these chips after the primary extraction. If you want to use them in the primary fermentation, put them in a grain or hop bag for retrieval.  

Usage rate: is 3-10 grams per liter of wine.  We recommend trying one sample with 3 grams, one sample with 6 grams and one sample with 10 grams to determine the different intensities of our flavors and aromatics. 

1 ounce is 28.35 grams  1 gallon is 3.78 liters  5 gallons is 18.9 liters

SO:

3 grams per liter rate for 5 gallons would be 56.7 grams or 2 ounces. 
6 grams per liter rate for 5 gallons would be 113.4 grams or 4 ounces. 

You could put the chips in a hop or grain bag if you need easy retrieval, especially during a bucket fermentation.  A carboy with a number 10 bung opening would be work too.